Abstract
The low lying levels in N=50 isotones have been well described within the shell model framework. These calculations were performed assuming an inert neutron core and the valence protons occupying either the (,) or (,,,) orbits. With the advent of multidetector arrays the level schemes of these nuclei have been extended to high spin regimes (J=20-25ħ). The inclusion of neutron core excitation (neutron particle-hole excitation across the N=50 shell gap) was essential to adequately describe these observed higher angular momentum states. Calculations involving neutron particle-hole excitation across the N=50 shell gap, coupled to the lower valence proton configurations, were not feasible due to computational limitations. This paper describes a truncation scheme devised to perform large basis shell model calculations. The level sequences observed in the N=50 isotones , , , and are interpreted on the basis of the shell model calculations in the configuration space , , , for the protons and , , , , , for the neutrons. The excitation of a neutron across the N=50 shell, into the next major oscillator shell describes the observed higher angular momentum states in these nuclei.
- Received 3 April 1995
DOI:https://doi.org/10.1103/PhysRevC.52.1881
©1995 American Physical Society